In dc motor starter there is less voltage required for holding contactor that's may why it is called no volt coil. but in ac starter why holding contactor is called no volt coil.

2 Answers   JSW,

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Why Lightning arrester used? Can we use piece of iron as a core material of transformer, if No, why? In CRGOSS material what is meaning of cold rolled grain oriented? Why Impegrenation of Transformer is done? Properties of Insulator? what is phase angle? Testing of transformers (Routine & Monthly)?

6 Answers   NTPC,

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How Negative Phase Sequence Relay works in case of Synchronous Motor?

4 Answers   L&T,

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what are the names of oil used in transformer and its chemical name?

11 Answers   Bhel, CSEB,

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why +24 v and -48 v give to BTS? If -48v protect from surge then why we not use -24 v?

0 Answers  

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why core losses are affected with change in voltege in transformer?

1 Answers   HCL,

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What is precision of a measurement?

0 Answers  

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Whats meant by trivector meter where it is connected at the substation?

20 Answers   GPIL, Infosys, Jakson, L&T, Secure Meters,

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why ELCB's are not useful for operation theater equipments ?

4 Answers   Reliance,

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What is the function of the circuit breaker failure relay?

0 Answers  

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In Panels Main Incomer considered should be TPN or FP?

2 Answers  

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How can we calculate the current if we have load in KVA and if the load in KW then what formula will be use for calculating the current. please give both the formula for calculating the current.

3 Answers  

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